Autocannon turret

"A heavy automatic turret. Its large-caliber shells do heavy damage over significant ranges, but its barrel must be refurbished after use. It cannot fire at close-up targets, and may explode when damaged."

The autocannon turret is a defense structure that fires a burst of high-damage shells. It has a maximum range of 32.9 tiles, but a per-tile accuracy of only 96% and cannot hit enemies within an 8.9 tile radius. Despite its damage though, the autocannon's stopping power is almost non-existent, not even being able to stagger humans - the same is also true for the uranium slug turret.

Since autocannons are large 2x2 structures, ranged attacks are twice as accurate against them. However, autocannons also benefit from being put behind sandbags which mitigates this accuracy bonus.

After firing 90 rounds it requires a barrel change, costing:

60 steel in Peaceful and Base Builder difficulty

90 steel in Medium difficulty

120 steel in Rough difficulty and above

Autocannon turrets have a chance to explode when they drop below 20% health, dealing damage to everything in a large radius.

Radius of autocannon turret explosion. Note the slight offset from the 'true' center of the turret.

Usage

Its use is not very cost-effective as its low accuracy makes it somewhat unlikely to land shots at range, and it costs quite some steel for each shot.

It can be useful in killboxes where it is more likely to hit, by bringing enemies closer together and putting them in range.

Due to their high damage output, autocannons can be effective at mowing down lancers when grouped, provided you can lure them within its effective range; their charge lances are otherwise able to outrange them by 4 tiles. Autocannons are also somewhat effective at dishing out damage against large targets such as centipedes since the accuracy bonus from their body size significantly offsets the autocannon's low accuracy, though centipede weapons can make relatively short work of autocannon turrets too.

Visualization of effective turret range of all three turrets, from uranium slug turret (top), to autocannon turret (middle), to mini-turret (bottom). Green is 80 - 100% of peak accuracy, blue is 50 - 80% of peak accuracy, red is below 50% of peak accuracy and grey is outside range. Gold tiles are spaced every 5 tiles.